I don't know if most people know this or not but in case it's not well known I thought I'd pass along this tip I got from a 30+ year experienced boat upholstery guy that did a little upholstery work on my boat a few years ago. I figured that with all of the years he's been restoring and repairing boat upholstery he'd know what he's talking about so I followed his advice and it has worked very well for me. As such, I can personally attest to this advice being good. He said the best product out there for keeping vinyl upholstery supple and to prevent it from drying and cracking and fading over time is good ol' WD40. I found that news to be very surprising but he said WD40 has a number of oils in it that vinyl loves and absorbs very well. He said to apply it in the cool shade by spraying it over a small section, allow it to soak in for a minute or so and wiping the area down with a rag to rub more of the oils into the material and wipe away any excess. Or you can spray one rag with lots of WD40, rub it into one small area of the upholstery, let it soak in for a bit and then wipe it off with another rag. Go along patch by patch until you've done all of the vinyl. If you have one person moving along applying it and another following behind doing the wiping and buffing, you can get a whole boat done very quickly.
Where I have my boat, once a year is plenty. Those of you who live in areas with a much longer boating season may want to do it a couple or more times a year, depending on the need. He said if you keep applying the WD40 year after year, your boat upholstery will look better and last much longer than it otherwise would and that in his experience, WD40 works as well or better than any expensive vinyl upholstery product out there but at a way lower cost.
I have applied WD40 to my boat's vinyl upholstery once a year for 3 or 4 years now and it has worked great for me. The vinyl has stayed very supple and lustrous and the colors still pop like when the boat was new. I know someone is going to ask about the smell and it's been my experience that the vinyl may smell a little like WD40 right at first but that goes away very quickly - like within an hour or less. The upholstery may also feel a little oily right after the WD40 has been applied but that also goes away very quickly. Thereafter, the vinyl just feels "fresh" and supple - like new vinyl.
The great thing about it is that it's incredibly cheap for how effective it is. Get one of those big economy sized cans and you probably won't use more than a buck or two's worth of WD40 to do your whole boat once over. Tough to beat for the price. If you're skeptical about this tip then just try it out in one small out-of-the-way spot and see how it goes.
Has anyone else used WD40 for treating/conditioning vinyl upholstery?